China's stock market index falls for 4th day, sinking 7.6 percent to 8-month low

China's main stock market index has fallen for a fourth day, plunging 7.6 percent to an eight-month low.

In Japan, the Nikkei 225 index, which had risen earlier Tuesday, closed down 3.9 percent at 17,806.70.

The Shanghai Composite Index closed Tuesday down 244.94 points to 2,964.97 amid sharp declines that have rattled investors abroad and triggered a global stock sell-off. It tumbled 8.5 percent Monday.

Chinese stocks have plunged over the last two weeks despite a multibillion-dollar government effort to stop a slide in prices.